Answer: pH = 3.15
Explanation: Solved in the attached picture.
Answer:
7.71x10^23 molecules
Explanation:
Avogadro's # = 6.022x10^23
1.28 mol SiO2 x 6.022x10^23/ 1 mol SiO2 = 7.71x10^23 molecules
Metallic bonding
The particles in a metal are held together by metallic bonds.
High melting and boiling points
Metallic bonds are strong and a lot of energy is needed to break them. This is why metals have high melting points and boiling points.
Conducting electricity
Metals contain electrons that are free to move in the metal structure, carrying charge from place to place and allowing metals to conduct electricity well.
Metallic bonding - Higher tier
Metallic bonding is the strong attraction between closely packed positive metal ions and a 'sea' of delocalised electrons.
Answer:
A) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly decrease.
Explanation:
A buffer is a solution which resists changes to its pH when a small amount of acid or base is added to it.
Buffers consist of a weak acid (HA) and its conjugate base (A–) or a weak base and its conjugate acid. Weak acids and bases do not completely dissociate in water, and instead exist in solution as an equilibrium of dissociated and undissociated species. When a small quantity of a strong acid is added to a buffer solution, the conjugate base, A-, reacts with the hydrogen ions from the added acid to form the weak acid and a salt thereby removing the extra hydrogen ions from the solution and keeping the pH of the solution fairly constant. On the other hand, if a small quantity of a strong base is added to the buffer solution, the weak acid dissociates further to release hydrogen ions which then react with the hydroxide ions of the added base to form water and the conjugate base.
For example, if a small amount of strong acid is added to a buffer solution that is 0.700 M H3PO4 and 0.700 M KH2PO4, the following reaction is obtained:
KH₂PO₄ + H+ ----> K+ + H₃PO₄
Therefore, [H₃PO₄] will increase, [KH₂PO₄] will decrease, and pH will slightly decrease.:
Definitely Calcium Chloride.
All the others are covalent.
